In the difficult and dangerous sports of rock and mountain climbing, it is often necessary to emplace various implements in the climbing surface from time to time to provide secure anchor points which may be used, for example, to receive a rope and provide vertical support thereto as the climbing surface is incrementally scaled and also to effect a safety stop in the event of a fall or slip.
A certain class of such implements are generally termed "chocks". A chock is provided with a loop at one end and a crevice-engaging structure at the other end in order that it can be slipped into a crevice and wedged in place to effect the anchor point. In their simplest forms, chocks may be have no moving parts, and the crevice-engaging end may simply be a wedge shaped piece to which a loop structure is attached. Recently, however, more sophisticated chocks have come into use which employ complementary sliding wedges with a moving wedge element which may be drawn against a spring bias toward the climber for insertion into the crevice and then released to, in effect, increase the thickness of the effective wedge. Similar, more complex, chocks employ a cam action to obtain corresponding operation. Typical of the prior art chocks are those disclosed in U.S. Pat. Nos. 3,903,785 to Pepper, Jr.; 3,957,237 to Campbell; 4,082,241 to Burkey; 4,572,464 to Phillips; and 4,643,738 to Guthrie et al.
While these prior art climbing devices are meritorious, there nonetheless remains, in each example, a significant need for improvement in one or more of: the ability to conform to irregular crevice interior surfaces, structural strength, ease of one-handed operation, lightness, compactness, simplicity of structure, simplicity of manufacture and cost. It is to providing a climbing chock enjoying all these advantages that my invention is directed.